2019 macbook pro 16 overheating and shuts down, 2.3Ghz i9, 32Gig, Sonoma 14.2.1

First of all, uninstall all anti-virus apps, cleaning/optimizer apps, and third party security software by following the developer's instructions since these types of apps are not needed on a Mac and usually cause more problems than they solve because the interfere with the normal operation of macOS. CleanMyMac is one of the worst offenders. I would also recommend uninstalling TechTool Pro as well since there isn't much it is good for....anything important can be done better with other tools.

Effective defenses against malware and other threats - Apple Community

If you still have problems after uninstalling these apps, then run the third party app EtreCheck and post the complete report here so we can review it for clues. This app will only create a report which will help us analyze & assess your system and can be run from the Downloads folder.

My guess is this laptop has a bad Logic Board which unfortunately is very common for the 2018-2020 Intel Macs, but especially the 16" 2019 models. It would not surprise me if the EtreCheck report shows multiple Kernel Panics or even ProxiedDevice-Bridge panic logs.

You can try running the Apple Diagnostics to see if any hardware issues are detected, but the diagnostics rarely find problems even when there is an actual hardware issue. However, it never hurts to run it just in case it does find something.

You can also try disconnecting all external devices in case one of them is causing a problem.